When designing piezo motor controller I tested a lot of ceramic loudspeaker control chips. Now I'm uploading all the design files and pictures.

The first chip I tried was LT3572. It has a 0.9A 40V boost converter and 0.6A 2 channel h-bridge made from BJT transistors. This QFN package chip works with voltages 2.7 V up to 10V - classical one cell lipo targeting chip. Although it looked good, I didn't use it because I had an partly inductive load and voltage spices killed all output transistors. It is good for generating digital signals into a high voltage capacitive only load.

The first board was small and had only necessary components. The second one is quite application specific and has some weird design decisions like series capacitors and stuff like that.

With this board I learned that wrong soft start capacitor will blow your circuit, tens of times.. Also that soldering a QFN to self made board is nearly impossible.